Benjamin Franklin suggested people set their clocks ahead in the summer as far back as 1784. The first systematic use of Daylight Saving Time did not occur until the Germans began setting clocks ahead in World War I to conserve fuel. Soon, Britian and other Western European countries had also adopted "Summer Time."
The U.S. observed this time change nationwide in 1918 and 1919 and again in World War II from February 9, 1942, through September 30, 1945.